The
Flynn Effect for Different Countries

Below are the rates of IQ gain per
year for different locations as found by James R. Flynn in Massive IQ Gains
in 14 Nations: What IQ Tests Really Measure, Psychological Bulletin,
1987, Vol. 101, No. 2, pp. 171-191. The tables are adapted from Table 15
of that paper.

In culturally reduced (non-verbal)
tests there is minimal reliance on learned content. Other tests only assess
verbal (learned) IQ. But the most famous tests examine both.
For example, the Wechsler tests have both a ‘Performance’ scale and a ‘Verbal’
scale . Flynn found the highest gains in the culturally reduced tests.
The lowest gains were in verbal tests. Intermediate gains were seen in
mixed tests such as the Wechsler and Binet, and in these tests, the performance
side had the higher gains.

In the following book various authors offer hypotheses to explain the Flynn Effect:

The first table below is a selection of columns
from the table as Flynn gave it: grouped by type of test. As was just mentioned,
the different types of tests give different magnitudes of gain, so countries
are best compared within that context. But because some people will likely
be interested in straight comparison between all the countries, a second
ungrouped ranking is given. I added the "type of test" column in both tables.

A few things to note:

1) The data from some countries are
more tentative than others. It is best to get a full explanation of this
from the paper.
2) The data only compares countries
in terms of IQ gain and so one must not draw hasty conclusions. It does
not say where they started from so how can you determine who is leading?
One exception is the Japan/US data on the performance scale of the WISC.
Since the performance subtests of the US WISC were "essentially unaltered
in the Japanese version", one can compare apples to apples. Over 1951 to
1971, the Japanese gains were 7.2 points higher than the US gains. If you are interested in seeing proper comparisions of the average IQs of various countries, click here.
3) The data are given on a 15 point
Standard Deviation Scale.

IQ Gains: Locations Grouped by Type
of Test and Ranked by Rate of Gain

Location

Test

Type of Test

Rate

Leipzig,
East Germany

Ravens

Culturally Reduced

1.250

France

Ravens

Culturally Reduced

1.005

Belgium

Ravens

Culturally Reduced

0.794

Belgium

Shapes

Culturally Reduced

0.716

Netherlands

Ravens

Culturally Reduced

0.667

Norway

Matrices

Culturally Reduced

0.629

West
Germany

Horn-Ravens

Culturally Reduced

0.588

Australia

Jenkins

Culturally Reduced

0.490

Edmonton,
Alberta, Canada

Ravens

Culturally Reduced

0.402

Australia

Ravens

Culturally Reduced

0.337

Norway

Matrices

Culturally Reduced

0.217

Great
Britain

Ravens

Culturally Reduced

0.189

Great
Britain

Ravens

Culturally Reduced

0.181

Japan

Wechsler

Mixed

0.835

Vienna,
Austria

Wechsler

Mixed

0.824

West
Germany

Wechsler

Mixed

0.741

Zurich,
Switzerland

Wechsler

Mixed

0.652

Edmonton,
Alberta, Canada

CTMM

Mixed

0.525

France

Wechsler

Mixed

0.380

United
States

Wechsler-Binet

Mixed

0.300

United
States

Wechsler

Mixed

0.243

Solothurn,
Switzerland

Wechsler

Mixed

0.186

Saskatchewan,
Canada

Otis

Verbal

0.628

Norway

Verbal-Math

Verbal

0.582

Belgium

Verbal-Math

Verbal

0.408

France

Verbal-Math

Verbal

0.374

Saskatchewan,
Canada

Otis

Verbal

0.348

New
Zealand

Otis

Verbal

0.242

Norway

Verbal-Math

Verbal

-0.133

IQ Gains: Locations Ranked by Rate
of Gain

Location

Test

Type of Test

Rate

Leipzig,
East Germany

Ravens

Culturally Reduced

1.250

France

Ravens

Culturally Reduced

1.005

Japan

Wechsler

Mixed

0.835

Vienna,
Austria

Wechsler

Mixed

0.824

Belgium

Ravens

Culturally Reduced

0.794

West
Germany

Wechsler

Mixed

0.741

Belgium

Shapes

Culturally Reduced

0.716

Netherlands

Ravens

Culturally Reduced

0.667

Zurich,
Switzerland

Wechsler

Mixed

0.652

Norway

Matrices

Culturally Reduced

0.629

Saskatchewan,
Canada

Otis

Verbal

0.628

West
Germany

Horn-Ravens

Culturally Reduced

0.588

Norway

Verbal-Math

Verbal

0.582

Edmonton,
Alberta, Canada

CTMM

Mixed

0.525

Australia

Jenkins

Culturally Reduced

0.490

Belgium

Verbal-Math

Verbal

0.408

Edmonton,
Alberta, Canada

Ravens

Culturally Reduced

0.402

France

Wechsler

Mixed

0.380

France

Verbal-Math

Verbal

0.374

Saskatchewan,
Canada

Otis

Verbal

0.348

Australia

Ravens

Culturally Reduced

0.337

United
States

Wechsler-Binet

Mixed

0.300

United
States

Wechsler

Mixed

0.243

New
Zealand

Otis

Verbal

0.242

Norway

Matrices

Culturally Reduced

0.217

Great
Britain

Ravens

Culturally Reduced

0.189

Solothurn,
Switzerland

Wechsler

Mixed

0.186

Great
Britain

Ravens

Culturally Reduced

0.181

Norway

Verbal-Math

Verbal

-0.133

A Commentary on the Flynn Effect and Other Points:

From what I have read in the scholarly literature, nobody denies that the Flynn
Effect exists. Throughout the world, data has shown that it is almost invariable
that modern generations do better on old IQ tests than earlier generations did.
Although the Flynn Effect continues to be surrounded by, and is central to several
controversies (for example, about the meaning of IQ, or g, or the validity of IQ
tests, or how the Flynn Effect can be explained) the Flynn Effect itself has survived
all scepticism.

James R. Flynn himself was perplexed by his findings (and he questioned the validity
of IQ tests). He was the one who brought up the rhetorical ploy of suggesting something
to the effect of that if IQs have been increasing by 3 points per decade, the ancient
Greeks must have been retarded to an absurd degree. One point that Flynn and others
gloss over is that there is no evidence, and no one is claiming that these IQ gains
have existed forever. Indeed, one of the theories that probably explains much of
the IQ gains is Richard Lynn's Nutrition Hypothesis (The Role of Nutrition in Secular
Increases in Intelligence, Personality & Individual Differences Vol.
11, No. 3, pp. 273-285, 1990). Lynn claims that nutrition improvements would explain
both the increases in height and in intelligence. In the above paper Lynn wrote:

For the last 2000 yr data on heights of adult males in Britain have been collected...
The broad trend is that height has been constant at a mean of approx. 172 cm up
to the cohort born around 1930. From this date onwards height has increased. It
seems reasonable to infer that brain size and intelligence were approximately stable
for about 2000 yr up to around 1930 and it is only in the last half century that
the increases have occurred.

By the way, doing Flynn Effect calculations is not something I invented. Flynn Effect
calculations can be found in the scientific psychological literature. Hence, when
you look at the Cox 300 geniuses list, you should really be looking at my Flynn
Effect corrected scores and not the original IQ score estimates if you want to compare
yourself to the Eminent Geniuses. If you have old IQ scores, you might want to do
your own Flynn Effect calculations. I realize that these calculations shrink the
pedestal that we keep the Eminent Geniuses on, but at least it should give more
of you hope that you might be able to accomplish important things (as long as you
are also gifted with creativity or perseverance or whatever other factors contribute
to grand achievements).